Gegenwärtige Projekte zur biologischen Bekämpfung aus Europa verschleppter Landwirtschafts- und Obstbau-Schädlinge

Summary The article briefly summarizes the work carried out by the European Station, C. I. B. C., during the period 1965–1971, in connection with attempts at the biological control of agricultural and orchard pest insects. The following species, their natural enemies and the present status of biological control operations are discussed: the European skipper,Thymelicus lineola Ochs. (for Canada), the pear psylla,Psylla spp. (for Canada), the cereal leaf beetle,Oulema melanopus L. (for Canada), the European marsh crane fly,Tipula paludosa Mg. (for Canada), the glasshouse thrip,Thrips spp. (for the U.K.), and the pear slug,Caliroa cerasi (for New Zealand).     

湖北省鸟类新纪录种——日本绣眼鸟

2022 年9 月29 日和11 月14 日,分别在湖北省荆门市钟祥市和湖北省武汉市汉阳区观察并 拍摄到日本绣眼鸟,经查阅文献确定为湖北省新纪录种。     

Performance of larval parasitoid,Bracon brevicornis on two Spodoptera hosts: implication in bio-control of Spodoptera frugiperda

Successful pest management using parasitoids requires careful evaluation of host-parasitoid interactions. Here, we report the performance of larval ecto-parasitoid wasp, Bracon brevicornis (Wesmael) on important agricultural pests, Spodoptera litura (Fabricius) and S. frugiperda (J.E. Smith). Biology of B. brevicornis was studied on different host instars under laboratory and cage setup. In no-choice assay, the parasitoid development was highest on fifth-instar S. litura larvae as the wasp laid?~?253 eggs with 62% hatching, 76% pupae formation and 78% adult emergence. Similarly, these parameters were highest on fifth instar S. frugiperda larvae (293 eggs, 57% hatching, 80% pupae formation, 70% adult emergence). In two-choice assay, B. brevicornis preferred fourth or fifth over third instar larvae of both hosts. Successful parasitism depends on host paralysis and suppression of host immunity. B. brevicornis interaction downregulated cellular immunity of both hosts as shown by reduced hemocyte viability and spreading. The percent parasitism rate of B. brevicornis was unaltered in the presence of host plant, Zea mays in cage study. 76 and 84% parasitism was observed on fifth-instar larvae of S. litura and S. frugiperda, respectively. We evaluated the performance of B. brevicornis as a biocontrol agent on S. frugiperda in maize field. Our results show 54% average reduction in infestation after release of B. brevicornis. Taken together, we report the performance of B. brevicornis on important insect pests for the first time in laboratory and field conditions. Our findings indicate that B. brevicornis is a promising candidate for integrated pest management.

     

Herbivory affects ovarian development in the zoophytophagous predator <Emphasis Type="Italic">Brontocoris tabidus</Emphasis> (Heteroptera,Pentatomidae)

The effect of prey-based and combination prey and plant-based diets [Tenebrio molitor pupae alone; T. molitor pupae and Eucalyptus cloeziana plants; T. molitor pupae and Eucalyptus urophylla plants; and T. molitor pupae and Psidium guajava (guava) plants] on the morphometry of the ovary of Brontocoris tabidus (Signoret) (Heteroptera: Pentatomidae) was analyzed in the field. Females fed on T. molitor pupae without plants presented with smaller ovarioles. The number of oocytes per ovary was higher for B. tabidus females fed on a combination diet of E. urophylla and T. molitor pupae when compared to females fed only on prey. In addition to diet, the number of oocytes in the ovariole was shown to vary with the age of B. tabidus. The 21-day-old B. tabidus females were found to have a higher number of oocytes per ovariole than the 15-day-old females in all diet conditions. The 15-day-old females exhibited more developed oocytes when fed on diets containing both prey and eucalypts plants and less developed oocytes when fed with a combination diet containing guava plants or T. molitor pupae alone. The 21-one-day-old B. tabidus females which were fed with a diet without plants had smaller oocytes than those fed with plants. Herbivory improves the morphology of the ovary of B. tabidus, affecting the size of the reproductive structures and the oogenesis of this natural enemy in the field.     

Beiträge zur Biologie der SchlupfwespePhygadeuon trichops Thomsom (Hym., Ichneumonidae)

Studies on the biology of Phygadeuon trichops Thoms. (Hym., Ichneumonidae.) Studies on the biology ofPhygadeuon trichops Thoms. (Hym., Ichneumonidae). Biological data, which were pointed out with one or several couples of ichneumonids per testcage, are reported such as life-span, reproductive capacity, duration of larval development, sex ratio, rhythm of oviposition, duration of copulation, supra parasitying, number of exit holes in the host pupa and the ratio of the F₁-progeny and real produced eggs. As host pupae for the ichneumonids pupae of the onion fly were used, which can be breeded easily in large scale.     

Effect of different host plants on the development time and parasitization rate of eretmocerus dehachi rose and rosen (hymenoptera: aphelinidae) withparabemisia myricae (Kuwana) (homoptera: aleyrodidae) as insect host

The effect of six citrus and five non-citrus host plants on the developmental time ofEretmocerus dehachi Rose and Rosen (Hymenoptera: Aphelinidae), the parasitoid ofParabemisia myricae (Kuwana) (Homoptera: Aleyrodidae), was studied under laboratory conditions. On citrus host plants, the mean developmental time from egg to adult was shortest on lemon with 14.6 days and longest on trifoliate orange with 26.3 days. On non-citrus host plants the developmental time ranged between 16.3 days on vine and 23.0 days on pomegranate. Among the various host plants tested,E. dehachi preferredP. myricae on sweet orange. A high mortality ofP. myricae due to host feeding and parasitization was observed on sweet orange and grapefruit among citrus host plants and on rose among non-citrus host plants.     

Stress resistance levels change little during dormancy in ash,sessile oak and sycamore seedlings

The physiological status of ash (Fraxinus excelsior L.), sessile oak (Quercus petraea (Matt.)) and sycamore (Acer pseudoplatanus L.) seedlings sampled from nurseries in Ireland between October and May, 1995/1996 and 1996/1997 was investigated. The results of heat treatments applied to taproots in vitro and evaluated using root electrolyte leakage (REL) indicated that sycamore was more easily damaged than the other species but lift date effects were small in all species. Dormancy release began later each year in ash (mid-November) than in oak or sycamore (late October to early November). The results of the REL and other data indicated that there was little change in stress resistance from November to about March (and April for some parameters). Sycamore was most active (highest shoot xylem pressure potential, REL, and root growth potential) during the winter, suggesting that adverse handling during this period is likely to reduce plant quality than in ash or oak. Field performance was good regardless of lifting/planting date.     

Pupal diapause development and termination is driven by low temperature chilling in Bactrocera minax

Bactrocera minax is a major citrus pest in China, Bhutan, and India. It is univoltine and exhibits pupal diapause during winter. To better understand pupal diapause in this pest, we investigated pupal survival and pupal developmental duration under field and laboratory conditions. Specifically, we tested if pupal chilling was required for diapause development and termination. Nearly all mature larvae collected at the end of the citrus season entered pupal diapause. For pupae exposed in the field, natural chilling for less than 3 months resulted in more than 70 % mortality. However, exposure to winter conditions for 3 months or more both decreased pupal mortality and developmental duration when pupae were returned to the laboratory and held under constant temperature (25 °C). When pupae were gathered from the field in November and exposed to different chilling regimes in the laboratory, the chilling duration (30 vs 60 days) had significantly more impact on pupal survival than the specific chilling temperature (6, 8, 10, or 12 °C constant). However, both chilling duration and chilling temperature impacted on the pupal developmental duration, with longer chilling duration and higher temperatures decreasing pupal developmental duration. In conclusion, we demonstrated that pupal diapause development and termination in B. minax is strongly influenced by chilling conditions. Increasing cold exposure led to significantly and consistently faster adult eclosion and improved synchronization of adult emergence. This knowledge will help with the laboratory rearing of B. minax, an essential step in the long-term management of this pest.     

Studies on biological control of the Bean-weevil (Bruchus chinensis L.) byApanteles flavipes (Cam.) (Hymen., Braconidae)

Bean-weevil (Bruchus chinensis L.) is commonly found in Sind region of Pakistan and it severely damages Mong seeds (Phaseolus mungo L.), and some other pulses in storage conditions. The parasitoidApanteles flavipes (Cam.), a gregarious Braconid parasite of Bean-weevil was reared under laboratory conditions with a view to exploiting it for the biological control techniques to be reported for the first time in Pakistan. This parasite completes its whole life cycle inside the body of the host by completing a number of generations in a year, and it successfully parasitisesBruchus spp. larvae inside the seed body; and its life cycle entirely depends upon the environmental factors like temperature and humidity as well as on the physiological condition of the host. It parasitised upto 45% in field population and 83% under laboratory conditions.     

Opportunistic changes in the host range of<Emphasis Type="Italic"> Lysiphlebus testaceipes</Emphasis> (Cr.), an exotic aphid parasitoid expanding in the Iberian Peninsula

Lysiphlebus testaceipes (Cr.), an exotic aphid parasitoid, but widespread along the West Mediterranean and Atlantic coastal areas, was regularly found in the northeastern part of the Iberian Peninsula parasitizing several aphid hosts, inland and in the Pyrenees. It was found that the environmentally induced restriction of available host species together with the opportunistic response and host alternation of the parasitoid contributed to the successful and on-going expansion and establishment of L. testaceipes from the coast to the inland montane areas of the Iberian Peninsula. Also, a comparison of the overall host range of L. testaceipes in several areas of the West Mediterranean/Atlantic (southern France, Spain, Portugal) demonstrated a rapid increase in the host range in these areas.     

The effect of season on the levels of predation by the ladybird <Emphasis Type="Italic">Serangium parcesetosum</Emphasis> Sicard (Coleoptera: Coccinellidae) on the cotton whitefly <Emphasis Type="Italic">Bemisia tabaci</Emphasis> (Genn.) (Homoptera: Aleyrodidae), a serious pest of eggplants

The whitefly Bemisia tabaci is a serious pest of eggplants, especially those grown undercover in polytunnels and greenhouses. Due to increasing levels of resistance of B. tabaci to a wide range of insecticides, there is now an urgent need to explore other non-chemical methods of control. In this study, Serangium parcesetosum, a ladybird, was evaluated as a possible biological control agent of B. tabaci’s winter and spring populations which infests eggplants grown undercover in Turkey. It was found that in winter, S. parcesetosum failed to control B. tabaci, even when the ladybird population was augmented six times over the course of the experiment. This contrasted with that observed in spring when, with only one introduction of the ladybird, control of the pest was gained within 3 weeks after release. In spring, the B. tabaci population in the cages receiving two and four S. parcesetosum adult per plant showed 56 and 53% reduction, respectively. The percent reduction in B. tabaci population rose to 98.6 and 98.3% in both cages, respectively, by the end of experiment. It is suggested that release of S. parcesetosum against B. tabaci during spring months may be offered as an alternative solution to increase implementation of biologically based B. tabaci management. In winter other biological control agents are needed and these need to be further explored.     

Studies on <Emphasis Type="Italic">Aleurothrixus floccosus</Emphasis> (Maskell) (Homoptera,Aleyrodidae) and its parasitoid, <Emphasis Type="Italic">Cales noacki</Emphasis> Howard (Hymenoptera,Aphelinidae) in the East Mediterranean Region of Turkey

Survey studies of Aleurothrixus floccosus (Maskell) (Homoptera, Aleyrodidae) and its parasitoid Cales noacki Howard (Hymenoptera, Aphelinidae) were made in 4 provinces; namely Adana, Mersin, Hatay and Osmaniye, which are the main citrus growing areas of the East Mediterranean region of Turkey. Inoculative parasitoid releases were made in regions where no or low natural parasitism occurred after obtaining preliminary results on presence of the parasitoid. The population dynamics of A. floccosus and C. noacki were examined in Silifke (Mersin), Dörtyol (Hatay) and Yüreir (Adana), where the A. floccosus population was remarkably high at the beginning of the study in 1999. However, after parasitoid release, the pest population declined in all the sites and did not attain the same high levels again. Five predators, three parasitoids and one entomopathogen species were determined as natural enemies of A. floccosus. In addition, seven plant species, six of them belong to Rutaceae, were found as host plants for A. floccosus.     

Behavioral responses,rate of mortality,and oviposition of western cherry fruit fly exposed to malathion,zeta-cypermethrin,and spinetoram

Western cherry fruit fly, Rhagoletis indifferens Curran (Diptera: Tephritidae), is a pest of sweet and tart cherry, Prunus avium L. (L.) and P. cerasus L., respectively, in western North America. This fly is commonly controlled with spinosad bait sprays. Spotted wing drosophila, Drosophila suzukii Matsumura, is potentially a new pest of cherries in this region that could be a threat to orchards at the same time as R. indifferens. Drosophila suzukii apparently is not controlled using spinosad bait sprays, but may potentially be controlled using malathion, zeta-cypermethrin, and spinetoram. However, how well these last three materials protect fruit against reproductively mature R. indifferens is not known. In laboratory observations, R. indifferens spent the least amount of time on cherries treated with zeta-cypermethrin, possibly because of its toxicity and irritant effects. In laboratory experiments, zeta-cypermethrin killed flies more quickly than malathion and spinetoram, causing up to 100% mortality 2 h after exposure. Zeta-cypermethrin prevented all oviposition when flies walked on dried residues for 20–25 min or were directly sprayed, and then exposed to cherries with dried residues, simulating exposure of mature female flies in a treated orchard. Malathion and spinetoram reduced oviposition compared with controls, but did not prevent it, when flies contacted residues or were directly sprayed at a high volume. Results suggest zeta-cypermethrin is the most effective of the three materials at protecting cherries against mature R. indifferens and could be used in an integrated control program for it and D. suzukii.     

Developmental threshold temperature and effective accumulative temperature of pupae and eggs of <Emphasis Type="Italic">Holcocerus hippophaecolus</Emphasis>

In order to understand the occurrence and the developmental regularity of seabuckthorn carpenterworm (Holcocerus hippophaecolus) and predict its population density, the developmental threshold temperature (C) and effective accumulative temperature (K) of the carpenterworm pupae and eggs were analyzed under the conditions of constant and variable temperatures. The results show that the values of C and K of the carpenterworm pupae are (12.1±0.2) °C and (295.2±4.1) day-degrees at constant temperatures, and (15.5±0.4) °C and (202.4±13.1) day-degrees at variable temperatures. However, the values of C and K of the eggs at variable temperatures are (16.7±0.8) °C and (101.5±12.6) day-degrees. The differences of developmental threshold and effective accumulative temperature under the conditions of constant and variable temperatures of the carpenterworm pupae accord with the developmental regularity of most insects in nature. By comparing five different constant temperatures, the conclusion is that the optimum developmental temperature of the pupae is 21 °C when both the pupation of the mature larvae and the eclosion of the pupae are very accordant. Moreover, the percentage of eclosion is over 90%. The average developmental durations of the carpenterworm pupae and eggs are 31 and 16 d at variable temperatures.     

Adaptive responses of<Emphasis Type="Italic">Acer ginnala,Pyrus ussuriensis and Prunus davidiana</Emphasis> seedlings to soil moisture stress

One-year-old seedlings of Amur maple (Acer ginnala Maxim), Ussurian pear (Pyrus ussuriensis Maxim) and David peach (Prunus davidiana Carr) were planted in pots in greenhouse and treated with four different soil moisture contents (75.0%,61.1%, 46.4% and 35.4%). The results showed that net photosynthesis rate (NPR), transpiration rate (TR) and stomatal conductance (Sc) of seedlings of the three species decreased with the decease of soil moisture content, and Amur maple seedlings had the greatest change in those physiological indices, followed by Ussurian pear, David peach. Amur maple and Ussurian pear seedlings also presented a decrease tendency in water use efficiency (WUE) under lower soil moisture content, whereas this was reversed for David peach. Under water stress the biomass allocation to seedling root had a significant increase for all the experimental species. As to root/shoot ratio, Amur maple seedlings had the biggest increase, while David peach had the smaliest increase. The leaf plasticity of Amur maple seedlings was greater, the leaf size and total leaf area decreased significantly as the stress was intensified. No significant change of leaf size and total leaf area was found in seedlings of Ussurian pear and David peach. It was concluded that Amur maple was more tolerant to soil moisture stress in comparison with David peach and Ussurian pear.     

Results and perspectives in the use ofBacillus thuringiensis Berl. var.kurstaki and other pathogens againstThaumetopoea pityocampa (Den. et Schiff.) in Italy (Lep., Thaumetopoeidae)

The pine processionary caterpillar,Thaumetopoea pityocampa is the most important defoliator of both native and introduced pines throughout Italy and is especially damaging in young plantations and on ornamental trees. A number of microbial pathogens have been isolated from larvae and pupae over the last 30 years. Some of them have been evaluated as biological control agents, and have provided encouraging results. However, onlyBacillus thuringiensis var.kurstaki (Btk) has passed the experimental screening and is now available for routine treatments, although its application by air is subjected to strict regulation by the government. The erratic performance of a single application ofBtk againstT. pityocampa that has been observed in the field (20–85% mortality) is related to a great variability in both the application dose and some population parameters ofT. pityocampa. The emergence period of adults varies from July (Alps) to October (South) and its duration is related to the spreading of the cohorts (individuals with different length of prolonged diapause) over time. In addition, embryonic development takes from 20 to 45 days, depending strictly on the temperatures recorded in the egg masses. As a result, the most vulnerable larval instars (L1 and L2) are never thoroughly reached by one application only, as the persistence of the bacteria on the needles is usually limited. Two applications are requested to control the pest in stands where the egg hatching occurs over more than one month. Another possibility consists of a single winter application against L3−L4 with a higher dose, to be performed where a certain amount of damage is tolerated.     

The biological efficacy of pear ester on the activity of Granulosis virus for codling moth

Ethyl (E,Z)-2,4-decadienoate (pear ester) is an adult and larval kairomonal attractant for Cydia pomonella (L.) (Lepidoptera: Tortricidae). The possibility of using a microencapsulated formulation of pear ester (DA-MEC, a.i. 5%, Trécé Inc.) to interfere with the host location behaviour was evaluated. Laboratory leaf disc bioassays and field efficacy trials were carried out on apple to determine the potential of improving the insecticidal performance of the granulovirus of C. pomonella (CpGV) by co-mixing with pear ester in a sprayable formulation. In laboratory bioassays, adding DA-MEC at low doses of CpGV insecticide increased the larval mortality as a function of time. The field tests performed revealed a significant effect of the blank DA-MEC formulation in reducing fruit injury compared to an unsprayed control.     

Pathogenic effects of <Emphasis Type="Italic">Xenorhabdus nematophilus</Emphasis> and <Emphasis Type="Italic">Photorhabdus luminescens</Emphasis> (Enterobacteriaceae) against pupae of the Diamondback Moth, <Emphasis Type="Italic">Plutella xylostella</Emphasis> (L.)

The relationship between Xenorhabdus nematophilus and Photorhabdus luminescens, the bacterial symbionts of the entomopathogenic nematodes Steinernema carpocapsae and Heterorhabditis bacteriophora, against the diamondback moth, P. xylostella (L.), pupae showed the pathogenic capability of P. luminescens to be over that of X. nematophilus. They gave 60 and 40?% mortality with LC₅₀ values of 5?×?10⁴ and 5.5?×?10⁵ cells/ml, respectively.The number of bacterial cells influences the rate of killing the pupae of P. xylostella and a direct correlation between mortality of the pupae, percentage of deformed adults and the spraying dose with significant differences were observed. An inverse correlation found between the no. of eggs laid/female, percentage of hatching, adult survival and the spraying dose. These bacterial effects have been attributed to different toxic bacterial enzymes which damage the haemocytes and inhibit activation of the humoral immune system of the insect.     

Host instar suitability of <Emphasis Type="Italic">Bemisia tabaci</Emphasis> (Genn.) (Hom.: Aleyrodidae) for the parasitoid <Emphasis Type="Italic">Eretmocerus mundus</Emphasis> (Hym.: Aphelinidae)

Efficient use of parasitoids in pest control depend on the knowledge of the biological relationships between host and parasitoid. Eretmocerus mundus Mercet (Hymenoptera: Aphelinidae) is one the most important natural enemies of Bemisia tabaci (Gennadius) (Homoptera: Aleyrodidae) that is found in fields and greenhouses in Adana, Turkey. Although more studies have been done to determine the relationships between E. mundus and B. tabaci, the differences among strains of E. mundus could have important biological concequences. In this study, biological characteristics of native population of E. mundus parasitization of B. tabaci (Q biotype) were determined using bean plants Phaseolus vulgaris (L.) at a constant temperature of 25 ± 1°C, relative humidity 70 ± 10% and 16:8 (L:D) photoperiod regimen. All B. tabaci nymphal instars were parasitized by E. mundus, but the mean number of daily-parasitized nymphs was highest in the second instars (15.3). In addition, second instar females had the shortest mean development time (15.2 days). Mean development times of parasitoids obtained from first, second, third and fourth B. tabaci instars varied from 15.2 to 16.2 days and 15.2 to 15.9 days for female and male, respectively. Proportion of female (♀/♂+♀) varied from first (0.53) to second (0.34) host instars. Impact of results on potential biological control of B. tabaci was discussed through conservation native natural enemies.